Re: Heat Riser problem

Posted by PackardV8 On 2007/8/16 20:14:02

The electric choke is only for choke operation. There is still some kind of exhaust manifol heat wheather thru the intake manifold or thru a hose from the exh manifold to the air cleaner snorkel. Many people thing the hose from ex manifold to air cleaner is some part of emmisions. It's not.

A certain amount of carb heat is necessary except under hi speed HOT conditions. Carburetor icing can occur at ambient temperatures as high as 50 degrees F. NOTE that many small air planes have MANUAL carburetor heat controls due to altitude and temperature changes. Cord L29 had a manual choke and a carb heat push pull knob on the dash.

My 56 Exec runs just fine without the heat riser even in very cold weather. HOWEVER, i have two different mufflers and one is a so-called turbo muffer so i'm guessing that a small amount of heat is always passing under the carb. It should yield better mileage. Also note that the 45XLS plugs area rather HOT plug which yields good cold engine performance.